I have said these things to you, that in me you may have peace. In the world you will have tribulation. But take heart; I have overcome the world.” (John 16:33, ESV)
Little children, you are from God and have overcome them, for he who is in you is greater than he who is in the world. (1 John 4:4, ESV)
For everyone who has been born of God overcomes the world. And this is the victory that has overcome the world—our faith (1 John 5:4, ESV)
Jesus makes two statements of fact. First, that you will have tribulation. Pain. Trial. Hurt. Suffering. It is both inside you and all around you. You are born into a broken earth. No amount of insulation or self-medicating will shield you from the difficulties that every religion in the world attempts to explain.
Second, "I have overcome the world". Jesus the God-man stooped to the level of man, to the level of death, to the level of the curse, and overcame it in love and righteousness. The holiness of the Christ could not be held by Hell. Acts 2 illustrates this. He was "crucified and killed by the hands of lawless men", but "God raised him up, loosing the pangs of death, because it was not possible for him to be held by it".
The first truth is easy to believe. No one needs to be told that no one is perfect, and that this place is painful. But it is reassuring that Christianity does not dismiss the reality of suffering as an illusion of our minds. But the second truth–that takes the victory of faith to believe (1 John 5:4). And, of course, it changes everything. The tribulation is no longer the main character, but a supporting role. There is a champion, a hero, a hope. I don't put much hope in the human race, except where the spiritual lifeblood of Jesus is transforming hearts, minds and communities. Is that a fact? No. That's a promise.